Liftxstg-jack



O. R. OSMUN.

LIFTING JACK.

APPLHIATION FILED APR. 10. 1919.

1,3 12,568, Patented Aug". 12, 1919.

Willi llll Ill/l/ v gnue'mioz THE COLUMBIA PLANOGRAPH :0. WASHINGTON. n c.

ORVILLE B. OSMUN, F COVING'ION, KENTUCKY.

LIFTING-JACK.

Specification of Letters Patent.

Patented Aug. 12, 1919.

Application filed April 10. 1919. Serial No. 289.046.

. at Govington, in the county of Kenton and State of Kentucky, have invented a new and useful Improvement in Lifting-Jacks, of which the following specification is a full disclosure.

ing lever. and contemplates a jack of this character which is raised or lowered inv stepped .movements by cooperating pawls and toothed standard or raised or lowered A in a single movement as when adjusting the jack toor from the load to be lifted.

An object of the invention is to provide a jack of this type in which the pawl move ments are controlled to determine the direction of jack movement and in which said control is accomplished by a lateral translation of the operating handle.

A further object is to provide for a quick and convenient removal of the handle from the jack. I

The features of the invention will be more fully set forth in the description of the drawings, forming a part of this specification, in which:

Figure 1 is a side elevation of the jack as adjusted for raising a load.

Fig. 2 is a similar view, partly in section, showing the adjustment for lowering a load.

Fig. 3 is a plan section on line 3, 3, Fig. 1.

Fig. 4 is a vertical section on line 4:, 4, Fig. 2.

Fig, 5 is a detail elevation of the inner end of the operating handle.

Referring more particularly to Figs. 1 and 2, a base 1 supports a toothed standard 3, having opposing series of ratchet teeth 4:, 5. A hollow lifting head 6- telescopically engages over the standard 3 and is provided with a cap or head 7 suitably formed for en gaging the object to be lifted and with a side ledge or step 8 for engaging objects at low elevation. The head 6 is retained in engagement with the. standard 3 by a pin 9 projecting intoan elongated slot 10 in said head and limiting the movement thereof. 11, 12, represent ears depending from the head 6 on either side of the standard 3. 13 represents an operating rock lever having a rectangular hollow frame portion 14E, pivoted at 15, 15, on the ears 11, 12 of the head 6, and a handle receiving portion 16,

which is slotted to receive the removable handle 17. Gravity ratchet pawls 18, 19, are positioned within the frame portion 1 1 of the rock lever 13 and are pivoted respectrvely on pivot studs 20, 21, at opposite sides of the toothed standard 3.

From the above it will be evident that a rocking movement of the lever 13 will cause the pawls to alternately engage the teeth of the standard to raise the j ack-head 6, and also to brin the head quickly into engagement with t e object to be raised. The lever 13 and head 6 may be bodily lifted by the handle 17, the pawls in this instance 7 idly ratcheting over the standard teeth. .After the head 6 is free of the load it may be quickly lowered by grasping the upper ends of the pawls and pinching them together to dlsengage their lower ends from engagement with the teeth of the stand- To provide for a step by step lowering operation, the following mechanism is employed:

Each of the pawls 18, 19, have trip fingers 25 projecting inwardly upon one side of the standard 3. A square shanked plunger 26 slides within a square cored recess in the head 6 and is urged downwardly by a spring 27. The lower end of the plunger is of stepped form providing a pawl engaging shoe portion 28 and a limb 29 alined with and adapted, when theaplunger is released,

' to engage the lever 13, thereby limiting the downward movement of said plunger. A control slide 30 has a beveled wedge nose 31 and a downwardly extending guide limb 32 slidable within a slot 33 in the lever 13. A square stud 34 projects laterally from said slide and engages into one of a pair of notches 36 formed in the opposite edges of the operating handle 17. This provides a unitary movement of the handle and slide.

InFig. 1 the handle 17 is shown pushed inwardly, the wedge nose 31 of the slide having engaged under and elevated the plunger 26 to raise its pawl engaging shoe portion 28 out of a pawl engaging position. When the handle 17 is withdrawn, as shown in Fig. 2 the slide 30 is removed from beneath the plunger and allows it to be forced downwardly by its spring. In this position the shoe portion 28 will alternately engage the pawl finger 25. As shown, the pawl 19 had been tripped during the upward movement of the operating lever. Upon lowering said lever the pawl 19 will engage the next lower tooth of the standard and after said pawl has come to rest the handle 17 is given a slight additional downward movement to elevate the pawl 18 causing its finger 25 to engage the plunger shoe 28 and trip said pawl for a subsequent lowering step movement of the head. The handle 17 can be quickly and conveniently removed by manually raising the slide 30 to disengage the square stud 8i from'the handle notch 36. A pin 38 prevents the slide 30 from bemg removed from the lever 13.

Having described my invention, I claim:

1. A lifting-jack comprising a standard, having opposed series of ratchet teeth, a lifting head slidably mounted on the standard, an operating member pivotally 0011- neoted to and movable with said lifting head, opposed ratchet pawls pivoted on the operating member at opposite sides of the having opposed series of ratchet teeth, a

lifting head telescopically slidable on said standard, operating mechanism carried by said head and cooperating with the standard for raising or lowering the lifting head, an abutment member movable to engage and control said operating mechanism, an oper ating handle and a device operated by said handle tor engaging the abutment member to render it mefliectwe.

4;. A lifting-jack comprising a standard having opposed series of ratchet teeth, a lifting head telescopically slidable on said standard, an operating lever pivoted on the lifting head intermediate of the opposed series of ratchet teeth of the standard, a pair of ratchet pawls respectively pivoted on the operating lever on opposed sides of the lever pivot and each cooperating wlth an adjacent series of ratchet teeth, a spring plun- I ger providing an abutment cooperating with and controlling the pawls, an operating handle slidably mounted upon the operating lever, and a device removably connected to and movable with the handle, adapted to engage and withdraw said abutment plun- V ger from cooperative relation with the ratchet pawls.

5. A lifting-jack comprising a toothed standard, a lifting head telescopically slidable thereon, an operatmg mechanism carried by said lifting hea'd, an operating handle, and means operated by a longitudinal movement of the handle for controlling the operating mechanism.

6. A lifting-jack comprising a toothed standard, a lifting head slidable thereon, a rocking operating mechanism for raising or lowering the lifting head by a step by step movement during each rocking movement of said mechanism, and a handle for rocking said operating mechanism, said handle being connected to hiave a relative independent movement, and means controlled by said independent handle movement for determining whether said operating mechanism shall raise. or lower the lifting head.

7 A lifting jack comprising a standard having opposed series of ratchetteeth, a lifting head telescopically slidable on said standard, an operating member pivotally connected to .and movable with said lifting head, opposed ratchet pawls pivoted on the operating member-at opposite sides of the standard, a spring member adapted to engage the pawls, a removable handle slidable relative to the operating member and a cam shde actuated by the handle to control the spring member.

8. A lifting-jack comprising a standard having opposed series of ratchet teeth, a

lifting head telescopically slidable on said standard, an operating nember pivotally connected to and removable with said lifting head, opposed ratchet pawls pivoted on the operating member. at opposite sides of the standard, means adapted to engage and control said pawls, a removable handle slidable on the operating member and having a notch and a. cam slide engaging into said handle notch and adapted to control said means.

9. A lifting-jack comprising a standard having opposed series .of ratchet teeth, a lifting hea'dftelescopically slidable on said standard, an operating member pivotally connected to and movable with said lifting head, opposed gravity ratchet pawls pivoted on the operating member at opposite sides of the standard, each having inwardly extending fingers, a spring pressed plunger carried by the lifting head adapted to be positioned to engage said pawl fingers, a handle slidable on the operating member and a cam slide slidable with said handle to control the spring plunger.

10. A lifting-jack comprising a standard having opposed series of ratchet teeth, a lifting head telescopically slidable on the standard, an operating member pivotally connected to and movable with said lifting head, opposed ratchet pawls pivoted on the operating member at opposite sides of the In Witness whereof, I hereunto subscribe standard, each having inwardly extending my name, as attested by the two subscribing fingers, control means adapted to engage Witnesses.

said fingers, a removable handle for rocking ORVILLE R. OSMUN. the operating member and a device detach- Witnesses:

ably connected to the handle for operating CLARENCE B. FOSTER,

the control means. a L. A. BECK.

copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. G. 

